BBC One aired the preview on its Children in Need fundraiser, reported Digital Spy.
The footage features Clara (Jenna Coleman) coming face-to-face with what appears to be Santa Claus (played by Nick Frost).
Peter Capaldi's Doctor then arrives to cast doubt on the red-suited one's motives and whisk Clara away.
Guest stars for the special include Natalie Gumede, Nathan McMullen, Michael Troughton and Faye Marsay.
'Doctor Who' series eight finale aired on BBC One on November 8 to an overnight audience of 5.45 million.